[Ifeffit] Problem with running mback algorithm in the newer version of Larch

Hello Matt, I found that while running the 'mback' algorithm there is an error in accessing f1_chantler database. Weirdly the commands work well for the older (0.9.35) version that happens to be installed on my old computer. But for the latest version (0.9.40), I simply could not able to generate the value of f1 and hence could not use the 'mback' algorithm. Do you have any suggestion to troubleshoot this issue on the latest version of the software? Also is there any inbuilt command to perform 'flattening algorithm' for normalization or one has to do it manually. Thanks, Akhil